Carburetor fuel valve



Oct. 3l, 1933. i RI F BRACKE A 1,933,043

CARBURETOR FUEL VALVE Filed July 25, 1929 E lllllllm its?? Patented Oct. 31, 1933 UNITED STATES n CARBURETOR FUEL VALVE I v Robert F. Bracke, Chicago, Ill., assignor, by

mesne assignments,

to Lynn' A. Williams,-

Evanston, and Clifford C. Bradbury, Glencoe,- Ill., as successor trustees Application July 25, 1929. -Serial No. 380,794

Claims.

My invention relates toimprovements in carburetor fuel valves.

An object of my invention is to provide an improved carburetor fuel valve.

A further object is to provide a carburetor fuel valve which does not become worn through use so as to jeopardize the seal between the valve and valve set when the valve is closed.

Another object is to provide a carburetor fuel valve in which the tendency to create a perfect seal between valve and valve seat actually increases through continued use.

A further object is to provide a carburetor fuel valve in which both the valve and the valve seat are constructed of soft metal. It has been customary in the past to construct the valve and often the valve seat of hard metal such as steel or monelto withstand as long possible the severe wear encountered.

Another object is to provide a carburetor fuel valve which may be manufactured aty a relatively low cost and is easily assembled.

Other objects and advantages will hereinafter appear.

An embodiment of my invention is illustrated in the accompanying drawing forming a part of this specication wherein: y

Fig. 1 is a schematic view illustrating a carburetor equipped with` my improved Vfuel valve;

Fig. 2 is a sectional view of the fuel valve;

and

Fig. 3 is a perspective view of parts of the fuel valve disassembled. l

kThe fuel valve illustrated in the drawing Vis one intended for use with a carburetor of the fuel lift type, wherein a diaphragm A isV subjected to a depression on that side which is exposed to the fuelV chamber Band to atmosbody as described is provided in a hexagonal shaped enlargement 13 on the outer wall of the body adapted to be received within the head of a socket wrench.

The body 10 is hollow or tubular and formed at its upper end with a depending internal annularange 14 forming the valve seat and de- Vfining a round opening through which a short stem 15 of the valve 16 extends. The valve 16 has the shape of a flat disc except for its upf standing stem 15 and therefore the Vupper surface of the disc may seat fully against the lower flat surface of the flange 14 to form a seal whether the valve shifts laterally or not.

A spring pressed plunger 20 is disposed within the body 10 and its lower end extends through an opening 21 in a spider 22 held securely against a shoulder 23 formed on the interior wall of the body 10, by a tubular plug 24 which is fitted within the lower end of ,the valve body by threads provided on the plug and the adjacent body wall. s

The upper end of the plunger 20 carries a flat square head 30, the corners of which are rounded as shown at 31 to conform with the .body Wall between which and the spider 22 a compression spring'32 encompassing the plunger 20 is disposed. The upper side of the head 30 vhas an upstanding disc-like projection 33 with a flat upper surface 34 which is caused to bear directly against the flat under-surface of the valve 16. The valve 16 is thus normally closed against its seat by the force of the compression sprng32. f'

In order to insure against an unnecessary wear ofthe diaphragmA a plate 35, having a downwardly extending skirt 36, is disposed between the diaphragm and the stem 15 of the valve pheric pressure on its opposite side C ,so that -16 so that the diaphragm does not directly 40 the diaphragm is caused to flex by a differential in pressure and thus operate the fuel valve.

The depression in the fuel chamber B is maintained by a Venturi tube fuel nozzle D extending within the induction passage E of the carburetor, the throat of which nozzle communicates with the fuel chamber B. Thus the relatively high depression existing at the constricted throat of the Venturi is utilized to control the opening of the fuel valve.

Referring now to Figures 2 and 3 of the drawing, the valve comprises a body l0 having an externally threaded portion 11 which is received in an internally threaded bore 12 formed in the bottom wall of the fuel chamber B. Means for facilitating the placing and the removal of the come into contact with the valve.

The plate 35 performs the additional function above the hexagonal venlargement 13. By ad- H justment of the nut 42 the proper tension may be brought upon the diaphragm A to'cause the opening of the valve 16 at any desired fuel chamber depression.

The nut 42 is held against displacement from i its adjusted position by a spring pressed pawl 50 which engages with the knurled outer wall of the nut.

When the valve 16 is opened signifying that a Y* lio Both the valve 16 and its valve seatrli whichl may form an internal part of the body 10 are made of brass which is possible because of the.

large contacting area of the valve with its seat assuring against the wearing away of the 'parts in short time.

As a matterl of fact, in the operation of my improved fuel valve I have found through prolonged tests that the valve after intensive use tends to more perfectly form a seal when closed than when first assembled. This important Ycharacteristic of the valve is exactly oppositeto that which takes place in the use of the presenttype of fuel valve employed in carburetors for many years past. In the old type of valve it was customary to use a conically pointed shaft which point seated against a ring-shaped seat and was therefore known as a needle valve. In use rooves were quicklyworn in the conical point,

even though hard Ysteel or Monel metal were used, which, of course, resulted in faulty and irregular valve action. I have entirely overcome this obstacle in valve operation by the structure herein described.

The valve 16, regardless of its initial position with respect to its seat 14, will always be brought into proper engagement with the seat by the spring pressed plunger 20 and its head 30.

twill be noted that the relatively broad fiat contacting surfaces of the valve and valve seat lie in a plane transverse to the axis along which the valve is .caused to move. .The valve may thus rotate about its axis in use and probably does, which movement but further assures smooth and uniform contacting surfaces. Ex'- treme wear through long usage does not in any way alter the gap through-'which fuel may pass between valve and seat when the valve isopened. This characteristic 'also is contrary to the needle type of fuel valve heretofore discussed, wherein grooves formed through wear cause a relatively sudden expansion of the gap when the needle is moved and thereupon by further movement-an increase in gap size of lesser amplitude.

I claim:

1. A carburetor :fuel valve comprising an annular valve seat having a relatively broad `-flat surface, a valve member having a seat engaging flat hard surface for engagement therewith'and adapted to move along an axis transverse to said flat surface, said valve member being further formed with that surface facing away from the valve seat fiat and parallel thereto, and a spring pressed plunger adapted to engage that surface facing away from the valve seat 'for moving the valve member into yielding engagement with its seat. Y 8G 2. A carburetor fuel valve comprising a valve seat, a valve member adapted to engage with said seat, the contacting surfaces of said valve member and said seat being relatively large and lyin a plane transverseto the axis along vwhich the valve member may move, a spring pressed plunger having a head adapted to bear against said valve member and yieldingly to hold the valve upon its seat, said plunger being arranged to move along an axis coinciding to the axis of the valve member whereby the same may be brought to fully bear against the seat regardless of slight'tilting or lateral displacement of the plunger.

3. A carburetor fuel valve comprising a valve seat, a valve member adapted to engage with said seat, the contacting surfaces of said valve member and said seat lying in a plane transverse to the axis along which the valve member may move, a spring pressed plunger having a head adapted to bear against said valve member and to yieldingly hold the valve member upon its seat, that surface of said valve member against which the plunger bears being flat and parallel with its seat vcontacting surface, said plunger be- 1.3.5 ing arranged to move along an axis coinciding with the axis of the valve member whereby the same may be brought to fully bear against the seat regardless of slight tilting or lateral displacement of the plunger.

4:. A carburetor fuel valve comprising an annular ilat surfaced valve seat, a valve having a broad flat surface adapted to engage said seat. the contacting surfaces of said valve and said seat lying in a plane transverseto the axis along which the valve may move, and spring pressed means having a at contacting surface adapted to bear'against said valve and to yieldingly move the valve against the seat, said valve being capable of rotation about its axis during movement i of said valve to assure a positive 'contacting surface with said seat at all times,

5. A carburetor fuel valve comprising a tubular body, a depending internal annular flange at its upper end forming a ilat valve seat, a valve .125 member having a fiat hard surface for contacting the fiat annular surface of said seat, said valve member being adapted to move along an yaxis substantially transverse to said fiat'surfaces, and Spring means 'engaging said valve member for .130

ieldingly holding the valve in engagement with the seat.

ROBERT F. BRACKE. 

